MOT defects · Suspension and steering

Suspension arm corroded MOT advisory: what it means and which cars get it

In DVSA MOT data for 2023, analysed by RegTail, testers recorded this as an advisory on at least 0.5 in 100 initial MOT tests. The Mazda 6 got it most often: recorded 4.9 times per 100 of its 67,869 tests.

DVSA wording: A suspension component excessively damaged or corroded.

Advisories

0.5 in 100

At least 182,907 tests in 2023

Most often

Mazda 6

4.9 per 100 tests

What it means

A suspension arm is rusting or damaged. As an advisory the tester has seen corrosion that does not yet weaken it enough to fail.

How serious it is

A major defect, so a fail, when excessively damaged or corroded. Fractured or likely to fail is dangerous.

Source: MOT inspection manual for cars and light vans, section 5.3.3.

Dangerous Fail
A direct and immediate risk to road safety or has a serious impact on the environment. Do not drive the vehicle until it's been repaired.
Major Fail
It may affect the vehicle's safety, put other road users at risk or have an impact on the environment. Repair it immediately.
Advisory Pass
It could become more serious in the future. Monitor and repair it if necessary.

What fixing it usually involves

Replace the arm, often with new bushes and ball joint included, then check the alignment.

A general guide, not a quote: ask a garage to inspect the car.

Which models get it most

Per 100 initial MOT tests on each model, among the 41 models with at least 20,000 tests where it is among the 40 most common items. DVSA MOT data for 2023, analysed by RegTail.

Model	Tests	Advisory
Mazda 6	67,869	4.9
Mazda 3	110,392	4.0
Ford Mondeo	216,645	3.9
Hyundai Getz	23,077	3.6
Mazda MX-5	95,311	3.5
Suzuki Grand Vitara	24,508	3.3
Land Rover Freelander	130,402	2.9
Alfa Romeo Mito	20,894	2.7
Hyundai Santa Fe	34,827	2.7
Audi TT	116,372	2.6

What to check at a viewing

On the car
Look at the lower arms behind each wheel for flaking rust, and at rear arms near the mounting points.
In the MOT history
If this appears as an advisory, see whether it came back at the next test or turned into a failure, and ask the seller for the receipt if it was fixed.

Check a specific car

Fleet averages only go so far. Enter the registration to see that car's own MOT history, mileage record and current condition, free.

Questions

What does "Suspension arm corroded" mean on an MOT?

A suspension arm is rusting or damaged. As an advisory the tester has seen corrosion that does not yet weaken it enough to fail.

Suspension arm corroded: is it an MOT fail?

A major defect, so a fail, when excessively damaged or corroded. Fractured or likely to fail is dangerous.

Which cars are most likely to get "suspension arm corroded" on an MOT?

In DVSA MOT data for 2023, analysed by RegTail, the models that got it most often were the Mazda 6 (4.9 per 100 tests), the Mazda 3 (4.0 per 100 tests), the Ford Mondeo (3.9 per 100 tests).

More suspension and steering defects

See every MOT defect we explain or MOT pass rates by model.

Coil spring broken or corroded Shock absorber leaking Shock absorber bush worn Suspension bush worn Suspension ball joint worn Anti-roll bar link worn Anti-roll bar link dust cover split Suspension joint dust cover split Track rod end worn Steering ball joint dust cover split Sub-frame corroded Suspension arm corroded CV joint boot split Wheel bearing play

How these figures are made. We counted the defects recorded at every initial MOT test (not retests) of cars and light vans in Great Britain in 2023 in the DVSA anonymised MOT dataset, 33,842,940 tests in all. Each item counts once per test. A failure is a major or dangerous defect, including one fixed during the test. A model's rate is the share of its tests where the item was recorded.

For each model we keep its 40 most frequent items, so a model where a defect is rarer than that is not listed, and figures for all cars are a floor. Defect names and explanations are ours, checked against the MOT inspection manual; DVSA's own wording is shown under each name.

Contains public sector information licensed under the Open Government Licence v3.0. RegTail's analysis of the DVSA anonymised MOT dataset, 2023 tests.